The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 11, 1998
Filed:
Feb. 26, 1996
Applicant:
Inventor:
Thomas E Haskett, Oakdale, MN (US);
Assignee:
Minnesota Mining and Manufacturing Co., St. Paul, MN (US);
Primary Examiner:
Int. Cl.
CPC ...
B03C / ;
U.S. Cl.
CPC ...
96 68 ; 55486 ; 55528 ; 55DI / ; 96 69 ; 442 36 ;
Abstract
There is provided a nonwoven electret fiber filter formed with a nonwoven web of electret fibers needle-punched to an open scrim support. The scrim support material has individual discrete open areas with an average cross-sectional area as viewed from the plane of the filter media of at least 0.25 mm.sup.2, preferably 1.0 mm.sup.2, and a pressure drop across the scrim support, without the filter web, of less than 1.5 mm H.sub.2 O measured at 98.4 meters/min gaseous face velocity. The resulting filter has enhanced lifetimes, a low pressure drop and high filtration efficiencies.